LITTLE ROCK (AP) — The Arkansas Supreme Court on Thursday ordered a new trial for a North Little Rock man convicted in the bludgeoning death of his grandfather, ruling that a judge didn’t properly instruct jurors on how to consider a lesser manslaughter charge.

Justices reversed Sean Fincham’s first-degree murder conviction in the January 2011 killing of his 65-year-old grandfather, Dennie Gregory. Fincham testified that he took a hammer from his grandfather during a confrontation and hit him with it.

In the 5-2 ruling, the court agreed with Fincham that jurors should have been told to consider the lesser charge of extreme emotional disturbance manslaughter independently of the murder charge. Instead, they were told they could only consider manslaughter if they had reasonable doubt on the murder charge.

“The jury was thus placed in an impossible scenario — it was instructed not to consider the offense of manslaughter unless it had reasonable doubt as to murder, but it was also instructed not to find guilt on manslaughter unless Fincham had committed a murder,” Justice Cliff Hoofman wrote in the majority opinion.

The court also asked its Committee on Criminal Jury Instructions to consider revising the instructions for the consideration of a lesser manslaughter charge.

Fincham, who was sentenced to life in prison testified that his memory blurred after that point and the next thing he remembered was standing amid blood and seeing his grandfather’s mutilated corpse in front of him. Prosecutors said Fincham used pliers to mutilate the body.

Fincher testified last year that his grandfather sexually abused him as a child and that he believed Gregory was doing the same thing to other family members.

Two justices disagreed with the majority’s ruling and said the jury’s instructions properly explained the law.

“Taken as a whole, the instructions in Fincham’s case accurately set out the whole law of the case, and presumably, the jury followed them,” Justice Karen Baker wrote in a dissenting opinion.